1H NMR studies of urine from premature and sick babies.

High-frequency proton nuclear magnetic resonance (1H NMR) has been applied to a study of urine from premature and sick newborn babies with a variety of clinical disorders. These included severe birth asphyxia, necrotizing enterocolitis, ketosis, and drug treatment. Abnormal levels of metabolites such as lactate, ketone bodies, betaine, dicarboxylic acids, and 4-hydroxyphenolic acids were detected, as was the antibiotic metronidazole and one of its metabolites. The assignment of betaine was confirmed by two-dimensional 1H NMR studies of urine obtained from two adults with homocystinuria receiving treatment with oral betaine. High-resolution 1H NMR spectroscopy of urine is a potentially useful research technique for monitoring metabolism during early life.